Blood tests

3 How to take

Always take Trimethoprim tablets exactly as your doctor has told you. If you are not sure, check with your doctor or pharmacist.

Swallow the tablets with a glass of water at the same times each day.

Doses:

Severe or sudden infections: (e.g. uncomplicated bacterial cystitis in women) treatment will usually be between 3-14 days, according to the type and severity of infection. Your doctor may double your first dose.

Adults and children over 12 years: 200mg twice a day.

Children 6-12 years: 100mg twice a day.

Children under 6 years: Not recommended; a more suitable dosage form should be used in this age group.

Long-term treatment and prevention therapy:

Adults and children over 12 years: 100mg at night.

Children 6-12 years: 50mg at night. The usual dose is around 2mg per kg body weight of the child per day.

Elderly: doses may be reduced in elderly patients, according to kidney function.

If you take more than you should

If you (or someone else) swallow a lot of tablets at the same time, or you think a child may have swallowed any contact your nearest hospital casualty department or tell your doctor immediately.

If you forget to take the tablets

If you forget to take a dose take it as soon as you remember it and then take the next dose at the right time. Do not take a double dose to make up for a forgotten dose.

If you stop taking the tablets

Do not stop taking Trimethoprim tablets because you feel better. Take the tablets for as long as your doctor has told you or your problem may come back.

4 Possible side effects

Like all medicines, Trimethoprim tablets can cause side effects, although not everybody gets them. Please tell your doctor or pharmacist if you notice any of the following effects or any effects not listed.

Contact your doctor at once if you get an allergic reaction such as swelling of the face, lips, tongue or throat, difficulty breathing, shock or collapse. Aseptic meningitis can occur in some patients. This may show as a combination of symptoms such as headache, fever, stiff neck, tiredness, feeling ill and your eyes become very sensitive to bright light.

Tell your doctor if you notice any of the following side effects or notice any other effects not listed:

Blood: altered number and type of certain blood cells. If you get increased bruising, nose bleeds, sore throats or infections you should consult your doctor. Too much potassium in the blood (you may experience muscle cramps or pain, irregular heartbeats, unusual tiredness or weakness).

Stomach: feeling or being sick, sore mouth, discomfort, this is usually mild and disappears after stopping the tablets.